Fixes #372

Before attempting to send mail, the hostname is retrieved using
socket.gethostname. If the hostname includes 'microbio.me', then mail is sent.
Otherwise, the user is dumped back to the portal with a message stating that
mail can be sent only from the microbio.me domain.
Merge branch 'master' of https://github.com/qiime/qiime_web_app into i372
Add function can_send_mail

takes no arguments, returns true if 'microbio.me' is in socket.hostname();
returns false otherwise
Adding doc string and streamlined fn
Modify files to use can_send_mail

Files should use can_send_mail from utils.mail instead of explicitly checking
whether or not 'microbio.me' appears in socket.hostname() return value
Merge branch 'master' of https://github.com/qiime/qiime_web_app into i372

Conflicts:
	www/americangut/submit_human_survey.psp
Fix ag_delete_participant

Fixes #505. This fix touches SQL code. ag_delete_participant now does not
remove samples, instead only removing logs and survey data. If samples also
need to be removed, that will have to be done separately.
Modify files that used ag_delete_participant

Added logic to remove samples only in places where it's needed to do so. Also
cleaned up some tabs/spaces heterogeneity in submit_human_survey.psp
Add squash_barcodes.py

This script (originally written by Daniel) is used to create a single
printable PDF from a collection of barcode images.
show project type of the barcode in barcode_util
Merge branch 'master' of git://github.com/qiime/qiime_web_app into barcode2
Add round4 barcodes to metadata select query
Adding Rob Steins resequenced barcodes
Checking in new verification icon for issue #522
Removing logic that changes the verification icon on the tab
Merge branch 'master' of https://github.com/qiime/qiime_web_app into verify_icon
Add shipping address to FAQ and mail tab

Fixes #528
Merge pull request #529 from adamrp/i528

Add shipping address to FAQ and mail tab
Add better error catching on add_participant.psp
Merge pull request #451 from adamrp/i372

Fixes #372